Interferon gamma release assays and tubercolin skin test performance in different settings of HIV immunodeficiency

In Vivo. 2015 Jan-Feb;29(1):137-40.

Abstract

Background/aim: HIV infection is a risk factor for re-activation of latent tubercolosis infection (LTBI). In recent years new blood tests for the detection of TB infection have been developed: Quantiferon TB Gold in Tube and TSPOT TB, which are interferon-γ releasing assays (IGRAs), have improved the identification of LTBI. In our study we have compared IGRAs and TST in HIV-positive patients with different settings of immunodeficiency.

Patients and methods: 98 consecutive HIV patients were recruited. They underwent a blood draw, a chest radiography and a tuberculin skin test. The HIV infection setting was detected and IGRAs were carried-out. Five patients showed a complete correspondence of TST, TSPOT-TB and QFT-IT. Discordant results were observed in patients testing positive to IGRAs but negative to TST. Only 2 patients showed positive TST and negative IGRAs.

Conclusion: Our study showed a poor concordance between tuberculin skin test and IGRAs, mainly in patients with a low CD4 cell count.

Keywords: HIV infection; Latent tubercolosis infection; interferon gamma releasing assays; tuberculin skin test.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antiretroviral Therapy, Highly Active
  • CD4 Lymphocyte Count
  • Female
  • HIV Infections* / drug therapy
  • HIV Infections* / immunology
  • HIV Infections* / virology
  • Humans
  • Interferon-gamma Release Tests* / standards
  • Latent Tuberculosis / diagnosis*
  • Male
  • Middle Aged
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Tuberculin Test* / standards
  • Viral Load
  • Young Adult